The statements in this section merely provide background information related to the present disclosure and may not constitute prior art. The system and method relate in general to wellbore cables.
Embodiments relate in general to winch tension control, such as for wireline cables and the like. A winch is used during oilfield operations to move a downhole tool up and down during logging measurement, such as during wireline operations. A tool is attached to the cable and lowered into the wellbore while the cable is spooled and/or unspooled on the drum. During conventional operations, the cable tension on the surface of the drum is a result of the type and length of the cable as well as the weight of the tool string attached to the cable. In conventional techniques, the tool enters the well due to gravity, wherein a winch operator controls the motion of the tool inside the well in manual mode.
Conventional gravity based logging technique can become a difficult, time consuming, at least potentially dangerous and sometimes impossible task when dealing with unconventional and/or deviated wellbore. Tough Logging Conditions (TLC) is a means of conveying a logging tool string when conventional gravity based wireline logging is not feasible. During a TLC operation, a wireline cable and toolstring is typically connected to the drillpipe or tubing and may be used with logging tools that are normally run on wireline. Control of the tension in the cable is essential for a successful TLC operation. A typical system used to control the cable tension is a hydraulic pressure limiting system, which may deliver poor performance, resulting in important tension peaks during speed variation (quick accelerations/stops). This uncontrolled increase of cable tension could lead to a situation where the weak point of the tool string could break, which would result in waste of time to repair, or in lose of the tool string.
It is always desirable to improve the operation of downhole tool winches and their associated spooled elements.